When you utilize a multi-tenant configuration for webNetwork where each tenant has their own DNS name and also utilize the public providers like Google, Dropbox, Box and Microsoft Onedrive you will have a problem where the dns names don't match up.
To solve this open webAdmin, find your relay configuration object. Go to the "Applications" tab, add the following Application Parameter:
OAuthCallback.host=your-main-webnetwork-server-dns-name.com
The host address should be the same as the host address used in the redirect URI on the storage provider when the application was created. Every tenant redirect URI will go back through that host instead of the tenant-host.